Oxygen therapy system



1965 w. HAUMANN ETAL OXYGEN THERAPY SYSTEM 4 Sheets-Sheet 1 Filed May 9,1963 INVENTORS WILFRIED HAUMANN CHARLES P.MULCAH Y g 19, 3935 w. HAUMANNETAL 3,199,303

OXYGEN THERAPY SYSTEM Filed May 9, 1965 4 Sheets-Sheet 2 INVENTORSWILFRIED HAUMANN CHARLES P. MUIZCAHY flnb/f 124/ ATTORNEY Aug. 10, 1 5w. HAUMANN ET AL 3,199,303

OXYGEN THERAPY SYSTEM Filed May 9, 1963 4 Sheets-Sheet 5 INVENTORS 39WILFRIED HAUMANN CHARLES P.MU! CA%EY Br Aug. 10, 1965 w, HAUMANN ETAL3,199,303

OXYGEN THERAPY SYSTEM Filed May 9, 1963 4 Sheets-Sheet 4 /4 INVENTORSWILFRIED HAUMANN 4 $4 2 CHARLES P.MULCAfi-Y United States Patent3,199,303 GXYGIEN THERAPY SilfiTEM Wiliried Haumann and Charles P.ltinlcahey, Indianapolis, Ind, assignors to Union Carbide Corporation, acorporation of New York Eiied May 9, 1963, Ser. l. o. 279,110 16 Claims.(Cl. 62-50) The present invention relates to a therapeutic system forsupplying oxygen as a breathing atmosphere and more particularly to asystem for use in medical therapy of pulmonary and cardiac disorders.

Physicians are increasingly prescribing physical exercise to the aged toencourage blood circulation, oxygen intake, and to normalize bloodpressure and pulse. In many cases, such prescriptions are not followedbecause the patient becomes short of breath, easily tires, and developspains and other discomforts. By inhaling oxygenenriched air in suchcases, these discomforts may be greatly reduced or eliminated enablingthe patient to continue his exercise and eventually resume activities ofhis normal life pattern. This is an increasingly important key point inthe medical treatment of pulmonary and cardiac disorders.

Unfortunately, however, present day medical oxygentherapy systems areeither immovable fixed-in-place types or so heavy as to be immovablefrom a practical stand point. Consequently, such therapy, if availableat all, is confined to special areas in a clinic or hospital set asidefor that purpose. The necessary flexibility in exercise patterns is notavailable when the patient is confined to such a special area.Furthermore, at-home therapy is eliminated because of the lack of anoxygen-enriched breathing atmosphere source. Also, when oxygen is neededfor patients confined to their beds, either at home or in a hospital,present day medical oxygen-therapy systems are handicapped because oftheir bulk and complexity.

It is an object of the present invention to provide a medicaloxygen-therapy system that is more convenient to employ than present daysystems. A further object is to provide an easily portable medicaloxygen-therapy system that an exercising patient may carry through hisexercises. Another object is to provide a bedside medical oxygentherapysystem that is less bulky than present day systems and is also moreconvenient to operate. These and other objects and advantages will beapparent from the following description and accompanying drawings, inwhich:

FIGURE 1 is a perspective view of the complete medi cal oxygen-therapysystem of the present invention;

FIGURE 2 is a view of a cross-section with some parts in elevation of aportion of a medical oxygen-therapy system embodying principles of thepresent invention;

FTGURE 3 is another view of a cross-section with some parts in elevationof another portion of a medical oxygentherapy system embodyingprinciples of the present invention;

FIGURE 4 is still another view of a cross-section with some parts inelevation of another portion of a medical oxygen-therapy systemembodying principles of the present invention.

COMPLETE THERAPEUTIC SYSTEM The present invention comprises a system forsupplying oxygen as a breathing atmosphere at a controllable rate from acompact and easily operable source. The apparatus of the present systemincludes a primary source of oxygen which is useful as a bedside medicaloxygentherapy system, a secondary source which is filled with oxygenfrom the primary source and is useful as a walkaround medicaloxygen-therapy system, and connecting means for effecting the transferof oxygen from the primary source to the secondary source which isconvenient and safe to employ for that purpose.

The primary source comprises a first double-walled container forreceiving and storing oxygen in the liquid state and for delivering thesame in a gaseous state as .a breathing atmosphere at controlled ratesupon demand therefor. The secondary source comprises a second smallereasily-portable double-walled container for receiving oxygen in theliquid state from the primary source and storing the same and fordelivering oxygen in a gaseous state at controlled rates upon demandtherefor. The connecting means comprises two sections, the firstconnected to the primary source and the second connected to thesecondary source such that the secondary source may be positionedrelative to the primary source quickly and easily. Use of suchconnecting means permits filling the portable secondary source withouthandling cold fittings and without using an inconvenient transfer hosearrangement. The connecting means also reduces frost formation andoxygen losses.

Both primary and secondary sources employ vapor venting means in gascommunication with respective first and second container storage spacesto maintain the pressures therein below maximum permissible levelsthereby preventing dangerous pressure buildups within the containers.Also, each source employs liquid oxygen vaporizing means to transformthe liquid oxygen to a breathable atmosphere, and breathing atmospheresupply means connected to the respective liquid vaporizing means in gascommunication therewith. In addition, the primary source may employmeans for maintaining the liquid oxygen in the first container atpredetermined operating pressure levels. The secondary source employsmeans for controlling liquid transfer into the second container.

Referring to FIGURE 1, the complete therapeutic system comprises aprimary oxygen source A, a second oxygen source B, and a connectingmeans C. Also shown in FIGURE 1 is a control panel D and a protectivecarrying case E which a patient may use to shoulder the portablesecondary source B as he moves about. This complete system and itsoperation is described in more detail with references to FIGURES 2, 3and 4.

Primary oxygen source As shown in FIGURE 2, the primary source Acomprises a storage container 10 having an outer jacket 12 spaced froman inner vessel 14 to define an evacuable insulation space 16 betweenthe inner and outer surfaces of the outer jacket and inner vessel,respectively. Inner vessel 1-;- is suspended from outer jacket 12 by athin, lowheat conductive neck tube 18 which defines an access passage 20to the inner vessel interior. Insulation space to is evacuated throughpinch-of tube 22 and preferably contains an opacified insulation of thetype described in US. Patent Nos. 2,967,152 and 3,007,596 for protectionagainst ambient heat inleak. Other insulation materials may be used butthe opacified types are the most efiicient insulations developed todate. A molecular sieve adsorbent 24-, of the type described in US.Patent No. 2,900,800, contained in blister 26, is preferably used tomaintain the vacuum within insulation space 16 by adsorbing residual gastraces remaining after insulation space 16 has been evacuated throughpinch-01f tube 22; by mechanical methods. A bursting disk 20, placed inouter jacket 12, prevents a dangerous pressure build-up from occurringwithin insulation space 16 should container it? develop a leak.

Means are provided about the top of access passage 2.0 to gas tightlyseal the interior of inner vessel 14 from the surrounding atmospheresuch as a spud 30 (FIG. 2) or a spud S-ii and cap 32 arrangement (FIG.3). in the preferred embodiment of the primary source A, a fluidtransfer tube 3d, a liquid vaporizi. g means 36, and the primary sectionof connecting means C (hereinafter called the connecting means C areconnected to spud 30.

Primary source A is preferably filled with pressurized and saturatedliquid oxygen through connecting means (For therapeutic applications, itis prererable that the stored liquid oxygen pressure be SllfIlCltllll tosupply gase: ous oxygen a pressure of about 50 p.s.i.g.) Liquid oxygenis transferred through connecting means C and fluid transfer tube 34into the bottom of inner vessel 14. Li uid level sensing means such asthermistors id and 32 are connected into a control circuit (not shown)to indicate the liquid level in container 10. This control circuit maybe arranged to control the filling of primary source A automaticallyfrom a liquid storage supply (not shown) if desired. a

When supplying oxygen to a patient, it is essential that only liquidoxygen be withdrawn from primary source A through fluid transfer tube toprevent an increase in hydrocarbon impurities found in even the highestpurity oxygen. If vapor were withdrawn, the higher-boiling hydrocarbonimpurities in tle remaining liquid would increase in concentration andcould deleteriously afiect the oxygen as a breathing atmosphere. Also,build-up of hydrocarbons in the liquid could cause a combustion hazard.By withdrawing only liquid oxygen, the purity of the remaining liquid isalways maintained at a high level inasmuch as the saturated liquid oxgen and vapor in the primary source A are maintained at substantiallyuniform and constant purity.

When the primary source A is used to supply oxygen directly to apatient, pressurized and saturated liquid is withdrawn through fluidtransfer tube 34 into liquid vaporizing means Gaseous oxygen from liquidvaporizing means 36 is conducted through conduit manual valve 44 to abreathing device such as an oxygen mask (not shown).

Liquid vaporizing means 36 comprises an ambient airwarmed or superheatercoil that extends from spud 3% down toward the bottom of primary sourceA and then winds upward around the outer jacket 12 to valve 44. Thelength of the liquid vaporizing means 36 must be suiiicient tocompletely vaporize and adequately superheat the withdrawn oxygen to abreathable atmosphere. This len th will depend on such factors as themaximum quantity that would be withdrawn at any time, the temperature towhich the oxygen would be superheated, and the temperature of thesurrounding atmosphere with which the oxygen in the superheater coil isheat exchanged. A hood is positioned around liquid vaporizing means 36in manner such that the latter cannot be bumped into or touched but alsosuch that sufficient air can circulate around the coils to vaporize andsuperheat the oxygen therein. A drip pan 4% collects condensed moisturefrom the coils.

Primary source A may be filled with liquid oxygen at atmosphericpressure and then pressurized such that the liquid oxygen therein issaturated at the desired working pressure. The embodiment of primarysource A shown in FIGURE 3 provides this feature. Cap 31 in FIGURE 3 maybe removed and liquid oxygen poured into the interior of inner vessel M.If desired, primary source I may be filied with non-pressurized liquidoxygen through connecting means C as in FIGURE 2 without removing cap Ineither case, an inner vessel pressurizing means 50, as in FIGURE 3, inconjunction with a pressure controller '52. having a pressure switch 54must be provided to pressurize the inner vessel and to maintain suchpressure at a predetermined level.

Liquid oxygen saturation may be maintained in the FIG. 3 embodiment ofprimary source A by pressurizing means 50 which comprises a resistanceheater 56 enclosed by a casing 58. Pressure switch 54, a pressure reliefvalve 6th and a pressure bursting disk 28 are connected to cap 32 suchthat they are in communication with the inner vessel interior. Pressureswitch 54 is normally open when the stored-liquid pressure correspondsto a predetermined level and closes when the liquid pressure falls belowthis level. The closing of pressure switch 54 causes a current in wires64 to energize heater 56. A thermal safety switch as is incorporatedinto the pressurizing circuit as a safety device to prevent heater 56from over heating the inner vessel 14. If the liquid level is too low,and heater 56 is activated before the inner vessel is refilled, thermalswitch 66 will be heated and break the pressurizing circuit before anydamage results.

An alternative embodiment of liquid vaporizing means 36 in FIGURE 2 isalso shown in FIGURE 3. When the primary source A of FIGURE 3 is used tosupply oxygen directly to a patient, pressurized liquid is transferredthrough fluid transfer tube 34 into liquid vaporizing means 36. Gaseousoxygen from liquid vaporizing means 36 is conducted through manual valve44 (which may include a rotometer as if desired) which controls the howof ox gen to a breathing device such as an oxygen mask (not shown).Liquid vaporizing means 36 comprises a hollow tube 7 9 containing anelectrical heater 72 and having external, helical grooves '74 for thepassage of liquid and vapor. The helical portion 74 of tube '72 may beconstructed from any thermally conductive material such as brass oraluminum. Thermal switches 76 and 73 control heater 72 to maintain apredetermined temperature level in the gaseous oxygen leaving liquidvaporizing means 36. Thermal switch 78 is preferably positioned adjacentheator 72 to provide better temperature control when the vapor flow isquickly reduced thereby preventing excessive heating of the vapor thatcould result if only thermal switch '76 were employed.

A tube 80 which connects liquid vaporizing means 36 with fluid transfertube 34 is held in alignment by means of counterbored screw 82. Thecounterbore in screw 82 forms a dead gas space which comprises an airgap that prevents cap 32 from frosting. The head of screw 82 is joinedto hollow tube of liquid vaporizing means 36.

In the two embodiments of primary source A shown in FIGURES 2 and 3, theliquid vaporizing means 36 of each are interchangeable and the liquidpressurizing circuit of FIGURE 3 could be used in the FIGURE 2embodiment. The preferred embodiment of FIGURE 2 is easier and moreconvenient to operate but, of course, there may exist situations wherethe FIGURE 3 embodiment would be preferable. For example, if liquidoxygen was not available in a pressurized and saturated form, apressurizing circuit such as the one in FIGURE 3 would be necessary.

Secondary oxygen source As shown in FIGURE 4, the secondary source Bcomprises a protective enclosure 83, a storage container 9d having anouter jacket 92 spaced from an inner vessel 94 to define an evacuableinsulation space 96 between the inner and outer surfaces of the outerjacket and inner vessel, respectively. The outer jacket 92 is preferablyconvoluted as shown at 93 for greater strength. Inner vessel 9 5 issupported within outer jacket 92 by a double-walled low-heat conductiveneck tube MM which defines an access passage MP2 to the inner vesselinterior. The annular space 104 between the concentric tubes of necktube iii-u is in gas communication with insulation space 96. Insulationspace 96 is evacuated through pinch-off tube 306 and preferably containsan opacified insulation of the type described in U.S. Patents 2,967,152or 3,007,596 for protection against ambient heat in leak. A molecularsieve adsorbent 1% of the type described in US. Patent 2,900,800 iscontained in blister I10 and maintains the vacuum within insulationspace 96. A bursting disk 112 placed in outer jacket 92 prevents adangerous pressure build-up within insulation space 96 from occurringshould the container 9t) develop a leak.

Means are provided about the top of access passage 1G2 to gas tightlyseal the interior of inner vessel 94 from the surrounding atmospheresuch as a spud 114 and cap 116 arrangement. In the preferred embodimentof the secondary storage source, a fluid transfer tube 118, a liquidvaporizing means 121), a pressure controller 122, and the secondarysection of connecting means C (hereinafter called the connecting means Care connected to cap 116.

When the secondary source 13 is used to supply oxygen directly to apatient, he opens the flow control valve 130 so that pressurized liquidis transferred through fluid transfer tube 118 into cap 116 andvaporizer means 120 which includes an ambient air-warmed or superheatercoil to a breathing device such as an oxygen mask (not shown). Flowcontrol valve 13% is provided with a dial (not shown) to enable thepatient to intelligently regulate the flow of gaseous oxygen.

To fill the secondary source, container it? is inverted to the positionshown in FIGURE 4 and placed on top of the primary supply source A shownin FIGURES 2 and 3, the primary and secondary connecting means C and Cbeing joined in a manner to be described subsequently. When the twosections C and C of connecting means C are properly joined, pressurizedliquid oxygen from the inner vessel 14 of primary source A willautomatically flow through fluid transfer tube 34, connecting means C,and fluid transfer tube 118 into inner vessel 94. During the filling ofthe secondary supply source B, vapor is vented from inner vessel 94 tomaintain a predetermined operating pressure level therein. Such vaporpasses through a vent tube 124, and a neck tube extension 126 thatconnects vent tube 124 and neck tube 100, into access passage 102, andthen to the atmosphere through cap 116 and the fittings attached toconnecting means C. A bursting disk 123 is connected to cap 116 toprevent damage to inner vessel 94 due to excessive pressures. Whenfilling is first begun, a small amount of liquid may flow intovaporizing means 120 but inasmuch as a flow control valve 1341 connectedto liquid vaporizing means 120 will not be open, the pressure build-upwithin liquid vaporizing means 120 will quickly terminate such flow.

During this filling operation, the liquid will fall to the end of innervessel 94 opposite the outlet of fluid transfer tube 118. As the liquidfalls, a shield 132 connected to neck tube extension 125 will protect aliquid level sensing thermistor 134 positioned therein. As the liquidlevel rises, a portion of the liquid will pass into shield 132 throughholes therein (not shown). On being contacted by liquid, thermistor 134will deactivate a solenoid valve in connecting means C to terminatevapor exhaust from inner vessel 94 thereby permitting the vapor pressuretherein to build-up to a suificient level to prevent further liquidtransfer into inner vessel M.

When the secondary supply source B is removed from atop the primarysource A on cessation of the filling procedure just described, containeras will be inverted from the position shown in FIGURE 4. In thisinverted position, as in the filling position, the vent tube 124 willalways be positioned in the vapor space of inner vessel 94. Thisprevents any liquid from being vented through the exhaust line which ismost important since the secondary supply source is designed to becarried by a moving patient and is relatively small (1.6 lbs. ofavailable liquid). Considering the small size of the secondary source,any liquid loss would be highly undesible. Further, from the standpointof safety, it would be very undersable for liquid to be vented duringuse by a patient because of the danger that the patient could be badlyfrost-bitten.

Connecting means The primary connecting means C is connected to the topof spud 313 (FIG. 2) or cap 32 (FIG. 3) of the primary source. Primaryconnecting means C comprises a double valve assembly 138 connected toconduits 38 and 39. Valve assembly 138 comprises two valve housings 1411and 142, each containing a valve, and a guide framework 148. Since thevalves are similarly constructed, valve 14-4 only is shown in detail inFIGURES 2 and 3 and described below to show the operation of both. (InFIGURE 3, valve housing 142 is behind valve housing and therefore notshown.) Valve 144 is made up of a threaded fitting and a spider nutwhich supports a valve-headed stem 15d. Valve housing 140 is connectedto valve 144 such that valveheaded stem 154 and a spring biased movablevalve seat 156 communicate with the interiors of valve housing 140 andconduit 38 to control fluid flow therebetween.

When the primary source A is used to fill secondary source B with liquidoxygen, liquid is transferred through fluid transfer tube 34, aroundvalve-headed stern 15 5 and through valve seat 15s into the secondaryconnecting ameans C attached to the secondary source B. If the primarysource is used to supply gaseous oxygen as previously described, theupper portion of fluid transfer tube 34 will be sealed from theatmosphere by the mating contact between valve-headed stern 154 andvalve seat 156. It is readily seen that primary source A may besimultaneously used as a gaseous oxygen supply source and a liquidsupply source for secondary source B.

Valve housing 142 (FIG. 2) is a part of the gas venting system ofsecondary source B and, as such, is only used when sources A and B areconnected for liquid transfer. During the filling of secondary source B,vapor is vented through valve housing 142, valve 146, solenoid valve158, relief valve 160, and gas diffuser 162. The operation of thisportion of the primary conr necting means will be described in moredetail subsequently.

The secondary connecting means C is connected to the top of cap 116 ofthe secondary source B (see FIGURE 4). This secondary connecting means Ccomprises a double valve assembly 164 consisting of valve housings 166and 168, which are attached to threaded fittings 170 and 172, one end ofeach of which threads into cap 116. A guide framework 174 is connectedto fitting 17d. Valve housing 166 is constructed such that a springbiased valve 176, enclosed there-in, provides fluid communication to theinterior thereof when displaced from a valve seat 178 in valve housing166. Valve housing 168 is similarly constructed.

Valve housing 163 is part of the gas venting system of the secondarysource and is only used when sources A and B are connected for liquidtransfer. During the filling of the secondary source, vapor is ventedfrom inner vessel 94 through vent tube 124, access passage 102, theinterior of the cap 116 into valve housing 168 and into valve 146 of theprimary connecting means C attached to primary source A. The operationof this portion of the second connecting means will be described in moredetail subsequently.

To position the secondary source on top of the primary source for liquidtransfer, the secondary source is inverted to the position shown in FIG.4 and the secondary connecting means C is seated on the primaryconnecting means C In seating these two sections of connecting means C,guide posts 180 of the primary connecting means guide framework 148 (seeFIGURES 2 and 3) are mated through apertures 182 of the secondaryconnecting means guide framework 174 (see FIGURE 4). A pair ofdouble-pronged levers 184 (part of which is not shown) is rotatablyattached to guide framework 148 by bolt 186 (FIGURE 2), and engages bolt13% (FIGURE 4) on guide framework 174 when these two sections areproperly mated to hold the two tightly together. tioning these twosections, valve housings 166 and 168 fit into valve housings 14th and142, respectively, and on tightly fixing these two sections, therespective movable On posivalve elements are displaced from their seatsto permit fluid transfer therebetween.

After the two sources are so connected, the liquid in the primary sourceis free to flow into the secondary source. Because of the pressuredifferential between containers 1t and $0, the liquid will immediatelybegin to flow into container 9% However, pressure within container 9@will almost as quickly build up to the point where the needed pressuredifferential will be eliminated. To counteract this pressure build uptendency, relief valve lot) (see FIGURE 2) is set to open at some lowpressure, such as 10 p.s.i.g. below the operating pressure of containeriii, and excess vapor from container 90 is permitted to vent throughconnecting means C to the atmosphere. As long as the liquid level incontainer 90 is below thermistor 134, solenoid valve 158 will remainopen and permit the excess vapor to vent through relief valve 160.Powever, when the liquid level reaches thermistor 13 i, solenoid valve158 will be inactivated thereby causing the pressure within container 96to build up to the point Where liquid transfer is terminated. Ontermination of liquid transfer, the two sources may be disconnected.

It should be noted that during filling, the vapors passing throughrelief valve tea are diffused into the atmosphere by gas diffuser 162.Such diffusion is highly desirable since it will prevent a dangerousincrease in oxygen concentration around the system and relieve anyanxiety that might be caused in the patient. Another advantage of thispressurized filling system is that the vented vapor system is attachedto primary source A. This permits attaching solenoid valve 158, reliefvalve 160, and diffuser 162 to the stationary primary source A thusreducing the weight and size of the portable secondary source.

Although preferred embodiments of the invention have been described indetail, it is contemplated that modifications may be made and that somefeatures may be employed without others, all within the spirit and scopeof the invention as set forth in the disclosure and claims.

What is claimed is:

ll. Apparatus comprising in combination a thermally insulated storagecontainer having an access passage in the top thereof to a storage spacewithin the container, means sealing said access passage and storagespace from the ambient atmosphere, a fluid transfer tube connecting tothe sealing means and extending through said access passage into saidstorage space and terminating adjacent the bottom thereof; vaporizingmeans connecting to said sealing means in fluid communication with saidfluid transfer tube, and connecting means connected to said sealingmeans in fluid communication with said fluid transfer tube for joiningsaid container to a second container to control fluid transfer betweenthe two containers, said connecting means comprising a valve assemblyhaving first and second valve housings, each containing a normallyclosed valve, and a guide framework, the first valve housing valve beingconstructed and arranged to permit liquid transfer through said fluidtransfer tube and the interior of said first valve housing into saidsecond container when said connecting means is joined to said secondcontainer, the second valve housing valve being constructed and arrangedto permit vapor venting from said second container through the interiorof said second valve housing when said connecting means is joined tosaid second container, and said guide framework being constructed andarranged to leak-tightly join said connecting means with correspondingmeans of said second container to permit the aforesaid liquid transferand vapor venting through said valve assembly.

2. Apparatus according to claim 1, including means for controlling thepressure within said storage space comprising a fluid heating elementcase extending into said storage space and having an interior portion incommunication with the space between the container walls, a fluidheating element in said fluid heating element case, and means forcontrolling said fluid heating element to maint3 tain the pressurewithin said storage space at a predetermined level.

3. Apparatus comprising in combination a thermally insulated storagecontainer having two spaced concentric walls and an access passage inthe top thereof to a storage space within the container; a neck tubedepending into said storage space having two spaced concentric inner andouter walls, upper portions of which being gas-tightly connected to thecontainer inner wall and outer wall, respectively, inner and outer walllower portions of which being gas-tightly connected together and thespace between the walls of which being in communication with the spacebetween the container walls, and the interior of said neck tube definingsaid access passage; means sealing said access passage and storage spacefrom the ambient atmosphere; a fluid transfer tube connecting to thesealing means for filling and emptying said storage space extendingthrough said access passage into said storage space and terminatingadjacent the bottom thereof; vaporizing means connecting to said sealingmeans in fluid communication with said fluid transfer tube; andconnecting means for joining said container to a second containercomprising a valve assembly connecting to said sealing means in fluidcommunication with said fluid transfer tube to control fluid transferbetween the two containers.

4. Apparatus comprising in combination:

(a) a thermally insulated primary storage container having an accesspassage in the top thereof to a storage space within the container,means sealing said access passage and storage space from the ambientatmosphere, a fluid transfer tube connecting to the sealing means andextending through said access passage into said storage space andterminating adjacent the bottom thereof; vaporizing means connecting tosaid sealing means in fluid communication with said fluid transfer tube;

(b) a thermally insulated secondary storage container having two spacedconcentric walls and an access passage in the top thereof to a storagespace within the container; at neck tube depending into said storagespace having two spaced concentric walls, inner and outer wall upperportions of which being gas-tightly connected to the container innerwall and outer wall respectively, inner and outer wall lower portions ofwhich being gas-tightly connected together, and the space between thewalls of which being in communication with the space between thecontainer walls, and the interior of said neck tube defining said accesspassage; means sealing said access passage and storage space from theambient atmosphere; a fluid transfer tube connecting to the sealingmeans for filling and emptying said storage space extending through saidaccess passage into said storage space and terminating adjacent thebottom thereof; vaporizing means connecting to said sealing means influid communication with said fluid transfer tube;

(c) and connecting means for joining the secondary container to theprimary container comprising: a primary guide framework connecting tothe primary container sealing means; a primary valve assembly connectingto said primary container sealing means in fluid communication with theprimary container fluid transfer tube and having (1) a first valvehousing connected to said primary container sealing means incommunication with said primary container fluid transfer tube, (2) afirst valve stem positioned in said first valve housing constructed tocooperate with a secondary valve assembly to open a normally closedsecond valve channel when the primary and secondary valve assemblies arecooperatively connected, (3) a first spring biased valve seatcooperatively positioned in said first valve housing to mate with saidfirst valve stem to provide a first valve channel normally closed to thetransfer of fluid from said primary container fluid transfer tube, (4) asecond valve housing in communication with the surrounding ambientatmosphere, a second valve stem positioned in said second valve housingand constructed to cooperate with a fourth valve housing when saidprimary and secondary valve assemblies are cooperatively connected toopen a normally closed fourth valve channel, (6) a second spring biasedvalve seat cooperatively positioned in said second valve housing to matewith said second valve stem to provide a third valve channel normallyclosed to the surrounding ambient atmosphere; a secondary valve assemblyconnecting to the secondary container sealing means in fluidcommunication with the secondary fluid transfer tube and having (1) athird valve housing connected to said secondary container sealing meansin communication with said secondary container fluid transfer tube andconstructed to cooperate with said first valve housing when said primaryand secondary valve assemblies are cooperatively connected, (2) a thirdspring biased valve seat cooperatively positioned in said third valvehousing to mate therewith to provide said second valve channel normallyclosed to the transfer of fluid to said secondary container fluidtransfer tube, (3) a fourth valve housing connected to said secondarycontainer sealing means in communication with the secondary containeraccess passage and constructed to cooperate with said second valvehousing when said primary and secondary valve assemblies arecooperatively connected to open the normally closed third valve channel,(4) a fourth spring biased valve seat cooperatively positioned in saidfourth valve housing to mate therewith to provide said fourth valvechannel normally closed to the transfer of vapor from said secondarycontainer access passage; and a secondary guide framework connecting tosaid secondary container sealing means, the primary and secondary guideframeworks being so constructed and arranged that said secondarycontainer may be inverted and positioned relative to said primarycontainer and said primary and secondary guide frameworks cooperativelyconnected to provide communication between the first and second valvechannels and between the third and fourth valve channels;

(d) means for controlling liquid transfer from said primary container tosaid secondary container when said primary and secondary valveassemblies are cooperatively connected comprising means for ventingvapor from the secondary container storage space into said secondarycontainer access passage so as to maintain the secondary storage spacepressure at a predetermined level below the incoming liquid pressure;and means for sensing the liquid level within said secondary storagespace during the filling thereof and for terminating the venting ofvapor from said secondary access passage through said third and fourthvalve housings when the sensed liquid level reaches a predeterminedheight so the secondary storage space pressure will equalize with theincoming liquid pressure thereby terminating liquid transfer into saidsecondary storage space.

5. Apparatus according to claim 4 including: means for controlling thepressure within said storage space comprising a fluid heating elementcase extending into said storage space and having an interior portion incommunication with the space between the container walls, a fluidheating element in said fluid heating element case, and means forcontrolling said fluid heating element to maintain the pressure Withinsaid storage space at a predetermined level.

6. Apparatus according to claim 2 wherein said means for controllingsaid fluid heating element to maintain the pressure within said storagespace at a predetermined level comprises: pressure sensitive meansconnected to said sealing means in communication with said storage spacefor sensing the pressure within said storage space and controlling theoperation of said fluid heating element in response to the sensedstorage space pressure so as to maintain liquid stored within saidstorage space in a saturated condition at said predetermined level.

'7. Apparatus according to claim 2 wherein said vaporizing meanssupplies vapor to breathing atmosphere supply means and comprises:

(a) elongated heating means having helical fluid passages along thelongitudinal periphery thereof when liquid is vaporized and superheated;

(b) and means for con-trolling the temperature of the superheated vaporsupplied from said vaporizing means to said breathing atmosphere supplymeans.

8. Apparatus according to claim 1 wherein said vaporizing meanscomprises an air-warmed superheater coil.

9. Apparatus according to claim 3 including means for controlling fluidtransfer to said container which comprises:

(a) means for venting vapor from said storage space so as to maintainthe storage space pressure at a predetermined level below the incomingliquid pressure;

(b) and means for sensing the liquid level within said storage spaceduring the filling thereof and for inactivating the aforementioned vaporventing means when the sensed liquid level reaches a predeterminedheight so that said storage space pressure will equalize said incomingliquid pressure thereby terminating liquid transfer into said storagespace.

10. Apparatus according to claim 5 wherein:

(a) said means for controlling said fluid heating element to maintainthe pressure within the primary storage space at a predetermined levelcomprises pressure sensitive means connected to said primary conduithousing means in communication with said primary storage space forsensing the pressure Within said storage space and controlling theoperation of said fluid heating element in response to the sensedprimary storage space pressure so as to maintain liquid stored Withinsaid primary storage space in a saturated condition at saidpredetermined level; and

(b) the primary vaporizing means supplies vapor to primary breathingatmosphere supply means and comprises elongated heating means havinglongitudinal peripheral helical fluid passages wherein liquid isvaporized and superheated and means for controlling the temperature ofthe superheated vapor supplied from said primary vaporizing means tosaid primary breathing atmosphere supply means.

11. Apparatus according to claim 4 wherein:

(a) said primary container guide framework comprises a plurality ofvertical guide posts aflixed to said guide post frame and means forlocking said primary and secondary containers together;

(b) and said secondary container guide framework comprises a guide framehaving a plurality of apertures therein to receive said primaryframework guide posts and means for receiving the means for locking saidprimary and secondary containers together.

12. Apparatus according to claim 3 including vapor venting means whichcomprises a vent tube connected to the inner end of said neck andconstructed and arranged to be positioned within the vapor space of saidcontainer in all attitudes of said container.

13. Apparatus according to claim 3 wherein said connecting meansincludes a guide framework connecting to said sealing means, said valveassembly and said guide framework being constructed and arranged suchthat said container may be inverted and positioned relative to saidsecond container with said guide framework and said valve assemblycooperatively connected to a corresponding second container guideframework and valve assembly to provide fluid transfer therebetween.

greases 14. Apparatus according to claim 13 wherein said valve assemblycomprises a valve housing connected to said sealing means in fluidcommunication with said fluid transfer tube and a spring biased valveseat cooperatively positioned in said valve housing to mate therewith toprovide a valve channel normally closed to the transfer of fluid in saidfluid transfer tube, said valve housing and said spring biased valveseat being constructed to cooperate with said second container valveassembly to open said valve channel when the valve. assemblies arecooperatively connected.

15. Apparatus according to claim 3 wherein said valve assembly comprisesfirst and second valve housings, each containing a normally closedvalve, and a guide framework, the first valve housing valve beingconstructed and arranged to permit fluid transfer from said secondcontainer through the interior of said first valve housing into saidfluid transfer tube when said connecting means is joined to said secondcontainer, the second valve housing valve being constructed and arrangedto permit vapor venting from said storage space through said accesspassage and through the interior of said second valve housing when saidconnectingmeans is joined to said second container, and said guideframework being constructed and arranged to mate said connecting meanswith corresponding means of said second container to permit theaforesaid liquid transfer and vapor venting through said valve assembly.

16. Apparatus according to claim 15 including means for controllingliquid transfer from said second container when said connecting means isjoined to said second container which comprises means for venting vaporfrom said storage space into said access passage so as to maintain thestorage space pressure at a predetermined level below the incomingliquid pressure; and including means for sensing the liquid level withinsaid storage space during the filling thereof and for terminating theflow of vapor from said access passage to the surrounding ambientatmosphere through said corresponding connecting means of said secondcontainer when the sensed liquid level reaches a predetermined height sosaid storage space pressure will equalize with said incoming liquidpressure thereby terminating liquid transfer into said storage space.

References Cited by the Examiner UNITED STATES PATENTS 1,505,095 8/24Heylandt 6251 1,901,445 3/33 Heylandt 6255 2,515,835 7/50 Preston 62502,528,780 11/50 Preston 6250 2,951,348 9/60 Loveday et a1 6250 2,964,91812/60 Hansen et al. 6255 2,998,708 9/ 61 Skinner 6245 3,049,887 8/62Sharp et al 62-55 FOREIGN PATENTS 267,703 9/29 Italy.

ROBERT A. OLEARY, Primary Examiner.

1. APPARATUS COMPRISING IN COMBINATION A THERMALLY INSULATED STORAGE CONTAINER HAVING AN ACCESS PASSAGE IN THE TOP THEREOF TO A STORAGE SPACE WITHIN THE CONTAINER, MEANS SEALING SAID ACCESS PASSAGE AND STORAGE SPACE FROM THE AMBIENT ATMOSPHERE, A FLUID TRANSFER TUBE CONNECTING TO THE SEALING MEANS AND EXTENDING THROUGH SAID ACCESS PASSAGE INTO SAID STORAGE SPACE AND TERMINATING ADJACENT THE BOTTOM THEREOF; VAPORIZING MEANS CONNECTING TO SAID SEALING MEANS IN FLUID COMMUNICATION WITH SAID FLUID TRANSFER TUBE, AND CONNECTING MEANS CONNECTED TO SAID SEALING MEANS IN FLUID COMMUNICATION WITH SAID FLUID TRANSFER TUBE FOR JOINING SAID CONTAINER TO A SECOND CONTAINERS TO CONTROL FLUID TRANSFER BETWEEN THE TWO CONTAINERS, SAID CONNECTING MEANS COMPRISING A VALVE ASSEMBLY HAVING FIRST AND SECONDD VALVE HOUSINGS, EACH CONTAINING A NORMALLY CLOSED VALVE, AND A GUIDE FRAMEWORK, THE FIRST VALVE HOUSING VALVE BEING CONSTRUCTED AND ARRANGED TO PERMIT LIQUID TRANSFER THROUGH SAID FLUID TRANSFER TUBE AND THE INTERIOR OF SAID FIRST VALVE HOUSING INTO SAID SECOND CONTAINER WHEN SAID CONNECTING MEANS IS JOINED TO SAID SECOND CONTAINER, THE SECOND VALVE HOUSING VALVE BEING CONSTRUCTED AND ARRANGED TO PERMIT VAPOR VENTING FROM 